The present invention relates generally to an earth working apparatus, and more particularly to an earth working apparatus having a sensor assembly attached thereto which detects relative position between various components of the earth working apparatus.
Earth working apparatus, such as excavators, typically have a frame, a first machine component, a second machine component and an articulating arm. The first machine component typically includes a track assembly. The second machine component typically includes a body assembly. The body assembly generally includes a cab and an engine enclosure. The frame is mounted on the track assembly. The body assembly is rotatably mounted on the frame. One end of the articulating arm is secured to the body assembly.
A motor is mechanically coupled to the body assembly such that an operator of the earth working apparatus can control rotation of the body assembly relative to the track assembly. For example, the operator can control rotation of the body assembly so as to position the articulating arm in a desired location for performing a digging function.
The motor for rotating the body assembly relative to the track assembly may be controlled by a computer located on the earth working apparatus. This computer must receive information relating to the spatial relationship between the body assembly and the track assembly in order to appropriately control rotation of the body assembly. One approach for providing the above described information to the computer is to attach sensors to the earth working apparatus which generate data regarding the spatial relationship between the body assembly and the track assembly. The data generated by the sensors is input into the computer so that the computer can appropriately position the body assembly relative to the track assembly in order to perform a work function such as digging. However, a problem with this approach is that such sensors are typically sensitive to adverse environmental conditions often found at excavation sites (e.g. moist or dusty environmental conditions). These sensors are also susceptible to damage from vibrations generated by the earth working apparatus. In addition, these sensors are prone to being struck and damaged by an object such as a rock.
It would therefore be desirable to provide an earth working apparatus having a sensor assembly attached thereto which better protects a sensor contained in the assembly from adverse environmental conditions. It would also be desirable to provide an earth working apparatus having a sensor assembly attached thereto which better protects a sensor contained in the assembly from vibrations generated by the earth working apparatus. It would further be desirable to provide an earth working apparatus having a sensor assembly attached thereto which better protects a sensor contained in the assembly from being struck and damaged by an object such as a rock.